CN102386937B - Wireless communication system and method for improving sensitivity of wireless communication system - Google Patents
Wireless communication system and method for improving sensitivity of wireless communication system Download PDFInfo
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Abstract
The invention discloses a wireless communication system and a method for improving sensitivity of the wireless communication system. The wireless communication system comprises a mobile communication antenna, a CPU (central processing unit) and a display module externally connected with the CPU, wherein a clock frequency of communication between the CPU and the display module is set, so that frequency values of nth harmonic wave and (n+1)th harmonic wave of the clock frequency avoid a receiving frequency band of the wireless communication system. In the invention, through changing the clock frequency, shielding, ensuring a Wlan antenna to be far away from the mobile communication antenna and improving signal completeness of an interface, wireless interference produced by higher harmonic radiated from a line to a system is weakened, thus wireless sensitivity of the wireless communication system is enhanced and system receiving performance is enhanced.
Description
Technical field
The invention belongs to wireless communication system technologies field, specifically, relate to a kind of for improving the method for wireless receiving sensitivity of communication equipment and the wireless communication system that adopts the design of described method.
Background technology
Along with the development of mobile technology and universal, mobile communication has obtained generally application in all kinds of portable terminals, especially over the past two years the products such as panel computer that rose, embedded multiple wireless applications such as second and third third-generation mobile communication 2G/3G network, Wlan (WLAN (wireless local area network)), bluetooth, GPS (global positioning system), mobile TV, really realized and integrated Mobile business, mobile communication, mobile entertainment.In the mobile Internet epoch, panel computer, with its brand-new mode of operation, abundant application experience, better mobility, becomes gradually the optimal combination product of PC and smart mobile phone, and ideally the function of the two is rolled into one.
Meanwhile, along with the function of electronic product from strength to strength, processor speed is more and more faster, the demand of miniaturization, portability is more and more stronger, has brought very large challenge also to the design of circuit board.The internal circuit of electronic product becomes intensive and complicated, and clock frequency approximately every two years will promote one times, and the problems of Signal Integrity of high speed circuit becomes more and more outstanding, and incident is exactly the problems such as sequential, noise, EMI (electromagnetic interference).When the frequency of these high speed signals or harmonic radiation out, by antenna reception and while entering the receiver of communication system, will have a strong impact on receptivity, cause wireless sensitivity, signal quality declines.
Summary of the invention
The object of the present invention is to provide a kind of method that improves wireless communication system sensitivity, to improve the wireless receiving performance of communication class electronic product.
For solving the problems of the technologies described above, the present invention is achieved by the following technical solutions:
A kind of method that improves wireless communication system sensitivity, in described wireless communication system, include mobile communication antenna, CPU and the display module external with CPU, the clock frequency of CPU and display module communication is set, makes the nth harmonic of this clock frequency and the frequency values of n+1 subharmonic all avoid the reception frequency range of wireless communication system; Described n is positive integer.
Preferably, the clock frequency that described CPU and display module communication is set is 108MHz.
For the wireless communication system that is provided with wireless local area network module, described wireless local area network module is connected to Wlan antenna, and be connected with described CPU, distance between Wlan antenna and mobile communication antenna is set, make two be less than-20dB of the isolation between antenna, with further improve described wireless communication system without line sensitivity.
Further, described CPU connects described wireless local area network module by its first group of SDIO interface, reduce the driving force of interface clock signal in first group of SDIO interface, and connecting series impedance build-out resistor on the clock cable of described interface clock signal, also can further play the effect that improves wireless communication system receptivity thus.
If think, further improve the wireless receiving sensitivity of wireless communication system, can adopt the driving force that reduces whole interface on software for described first group of SDIO interface, and connecting series impedance build-out resistor in each signal line of this SDIO interface, make the CPU at holding wire two ends and wireless local area network module reach impedance matching.
For the wireless communication system that is provided with storage card, can allow CPU pass through its second group of SDIO interface and connect described storage card, reduce the driving force of interface clock signal in second group of SDIO interface, and connecting series impedance build-out resistor on the clock cable of described interface clock signal, can weaken thus the impact that the read-write operation due to storage card causes the sensitivity of wireless communication system.
Further, if obtain the more desirable effect of improving, can on software, reduce the driving force of whole second group of SDIO interface, and connecting series impedance build-out resistor on all holding wires of second group of SDIO interface, make CPU and the storage card at holding wire two ends reach impedance matching, with improve wireless communication system without line sensitivity.
For the wireless communication system that is provided with DDR memory, described DDR memory can be connected to described CPU by parallel bus, described CPU, DDR memory and be connected to parallel bus between the two above radome is set or covers conductive fabric, to avoid consequent electromagnetic interference signal to radiate, affect system without line sensitivity.
Further, in described wireless communication system, also include power module, in described power module, be provided with power inductance, above described power inductance and connected cabling, be provided with radome or be coated with conductive fabric, to avoid the electromagnetic interference of power inductance and peripheral wiring generation thereof to external radiation, the sensitivity of wireless communication system is exerted an influence.
Method based on the sensitivity of above-mentioned raising wireless communication system, the present invention also provides the described method design of a kind of employing wireless communication system, comprise mobile communication antenna, CPU and the display module external with CPU, by the clock frequency of CPU and display module communication is set, make the nth harmonic of this clock frequency and the frequency values of n+1 subharmonic all avoid the reception frequency range of described wireless communication system, can solve thus the humorous wave interference that radiated by the clock line problem impacting without line sensitivity to wireless communication system when display screen is lighted, reach thus the purpose of design that improves wireless communication system sensitivity, described n is positive integer.
Preferably, described wireless communication system can be panel computer or smart mobile phone etc.
Compared with prior art, advantage of the present invention and good effect are: the present invention is changed clock frequency, shielding, improved the methods such as signal integrity and weaken the air interference that the high order harmonic component that radiates in circuit produces system by employing, promoted thus wireless communication system without line sensitivity, strengthened the receptivity of system.
Read by reference to the accompanying drawings after the detailed description of embodiment of the present invention, it is clearer that the other features and advantages of the invention will become.
Accompanying drawing explanation
Fig. 1 is the circuit framework schematic diagram of receiving unit in existing wireless communications system;
Fig. 2 is the clock signal trace-diagram of CPU and peripheral circuit thereof in wireless communication system;
Fig. 3 is the installation position schematic diagram of mobile communication antenna and Wlan antenna in classic flat-plate computer;
Fig. 4 is that the present invention is for improving the mobile communication antenna proposing without line sensitivity of system and the installation position schematic diagram between Wlan antenna;
Fig. 5 is the laying schematic diagram of the screen unit proposing without line sensitivity on system circuit board that the present invention be to improve system.
Embodiment
Below in conjunction with accompanying drawing, the specific embodiment of the present invention is described in detail.
In the receiver of mobile communication terminal, receiving sensitivity is very important index, is related to the distance of communication and the stability problem of signal.It is defined as, under the condition of output signal-to-noise ratio of giving provisioning request, and the minimum incoming signal level that receiver can detect, in GSM/TD-SCDMA (second generation/3G (Third Generation) Moblie technology) standard, unit generally represents with dBm.This index is relevant with the noise size of desired output signal-to-noise ratio, receiver.Sensitivity quantizes with following formula:
P
in(min)(dBm)＝-174(dBm/Hz)+10logBW+NF(dB)+SNR
o，min(dB)。
In formula, P
in (min)for minimum power input, unit is dBm; The-174th, the thermal noise power spectrum density of system in the time of 17 ℃, unit is dBm/Hz; BW is signal bandwidth, and unit is Hz; NF is receiver noise factor, and unit is dB; SNR
o, minfor exporting minimum signal to noise ratio, unit is dB.
In wireless communication system, the circuit system of its receiving unit adopts structure form as shown in Figure 1 conventionally, comprises the chief components such as mobile communication antenna, duplexer and filter, receiving circuit, baseband processor.Wherein, the mobile communication signal receiving by mobile communication antenna transfers to receiving circuit via duplexer and filter circuit and separates after mediation multistep treatment, and then transfer to baseband processor and carry out data processing, the vision signal of generation can be carried out output display by the display screen in system; The audio signal generating can be play output by the loud speaker in system or earphone.
In the system of wireless receiving part, often can run into two concepts: conducted susceptibility and without line sensitivity.Wherein, the mode by wired conduction between receiving system and signal source connects, and the sensitivity recording is conducted susceptibility, also claims to have line sensitivity.Mode by wireless coupling between receiving system and signal source connects, and the sensitivity recording is without line sensitivity.The theoretical value of conducted susceptibility can be calculated and obtain according to above-mentioned formula.The general GSM receiver of take describes as example, the noise factor NF=3dB of its receiver; Exporting minimum signal to noise ratio requires for SNR=6dB (the minimum signal to noise ratio that is baseband processor input port requires as 6dB); The bandwidth of gsm system is BW=200KHz, and, in Fig. 1, the minimum power input of receiving circuit input port is:
P
B(min)(dBm)＝-174(dBm/Hz)+10log(200×10
3)+3(dB)+6(dB)＝-112(dBm)
Because the loss of duplexer and filter is generally 3dB, the minimum power input at duplexer input port is:
P
A(min)(dBm)＝P
B(min)(dBm)+3(dB)＝-109(dBm)
That is to say ,-109dBm is the conducted susceptibility theoretical value of gsm system.
The efficiency of supposing mobile communication antenna is 50% (general GSM antenna may also not reach this value), is equal to the device of 3dB decay, so mobile communication antenna is taken into account to being without line sensitivity of whole GSM receiving system:
P
radiation(min)(dBm)＝P
A(min)(dBm)+3(dB)＝-106(dBm)
Above-mentioned computing formula is all under without external interference environment, the quantitative formula of sensitivity.But in actual open environment, interference signal always can mix with useful signal, arrives its output port after the multistep treatment by receiving circuit, and then affect the signal to noise ratio of baseband processor input port.When intensity one timing of input signal, the interference signal that enters into system is stronger, and the signal to noise ratio of receiving circuit input port is less, and the signal to noise ratio of receiving circuit output port is just less so.So, when having external interference signal, in order to improve the signal to noise ratio of receiving circuit output port, must improve the intensity of input signal.The minimum signal strength that system can receive so has just uprised, i.e. sensitivity variation.
As can be seen from the above analysis, in the situation that conducted susceptibility is definite, improves and have two kinds of methods without line sensitivity: a kind of is to improve antenna performance, and efficiency is uprised; The second is the interference noise intensity that reduces the system of entering.The present embodiment is paid close attention to the interference noise that enters receiving system to how to reduce, and to take the receptivity of the mobile communication GSM900 frequency range of panel computer and the 2G frequency range of TD-SCDMA be example, provide a kind of and search, locate, analyze, reduce the method for interference.
How to judge the quality without line sensitivity, can be by test receiver comprehensively judging without line sensitivity under each operating state.The panel computer of take describes as example, can light and extinguish by operation lcd screen, WLAN Wlan opens and closes, and the operation such as storage card read-write, use comprehensive tester test different channels without line sensitivity, if test result is less than national Specification-102dBm, think qualified products, otherwise, think substandard product.
In the circuit system design of panel computer, in the periphery of central processor CPU, need to connect multiple peripheral circuit, such as display module, wireless local area network module, jumbo storage card, DDR memory etc., shown in Figure 2.In actual test process, we find, interference noise generally produces by following approach:
(1) when the display screen of panel computer (take LCD screen describe for example) is lighted, from the clock cable being connected between CPU and display module, be easy to radiate high order harmonic component, form interference signal, to exerting an influence without line sensitivity of panel computer;
(2) CPU is carrying out in the process of data communication with its peripheral circuit, such as carrying out in the process of exchanges data with DDR memory, because the operating frequency of CPU is generally in 1GHz left and right, the signal of its transmission is all often high speed signal, therefore easily produce frequency electromagnetic waves, be radiated in system and just form electromagnetic interference, be incorporated on the mobile communication antenna of panel computer, i.e. impacting without line sensitivity system;
(3) after WLAN capability starts, the Wlan antenna that connects wireless local area network module can be used as the propagation path of interference signal, the interference signal that CPU from system board is produced is incorporated on the mobile communication antenna of panel computer, thereby affects the receptivity of system;
(4) after WLAN capability starts, from the interface clock line being connected between CPU and wireless local area network module, be easy to give off high order harmonic component, and just falling in the reception band limits of system, thereby producing obviously and affecting without line sensitivity system.
For the way of production of above-mentioned four aspect interference noises, the present embodiment has all proposed corresponding solution:
For above-mentioned (1) kind situation, the present embodiment, by the clock frequency of change CPU and display module communication, makes the nth harmonic of this clock frequency and the frequency values of n+1 subharmonic all avoid the reception frequency range of panel computer, and described n is positive integer.Thus, even give off humorous wave interference from the clock cable being connected between CPU and display module, can not exerting an influence without line sensitivity to system yet.
For above-mentioned (2) kind situation, the present embodiment is used shielding material to shield CPU and peripheral circuit thereof.For example: CPU and DDR memory and be connected to parallel bus between the two above radome is set or covers conductive fabric; For the HW High Way that connects CPU, also should be placed in described radome, the part that radome does not cover can be used conductive fabric to wrap up, and with the high-frequency electromagnetic wave excitation avoiding producing out, system is formed to interference noise.In addition, in the power circuit design of system, often need to use power inductance, when power circuit is worked, at power inductance place, also can produce high order harmonic component, therefore the present embodiment preferably arranges radome or parcel conductive fabric above described power inductance and external cabling thereof, to mask the electromagnetic interference by its generation, further improve the wireless receiving performance of system.
For above-mentioned (3) kind situation, the present embodiment adopts by Wlan antenna the design away from mobile communication antenna, makes two be less than-20dB of the isolation between antenna, to reduce the impact of Wlan antenna on mobile communication antenna.
For above-mentioned (4) kind situation, the present embodiment adopts the driving force that reduces the interface that CPU is connected with wireless local area network module from software, from hardware, connecting series impedance build-out resistor on the holding wire of described interface, so that reach the integrality that the mode of mating is improved signal between CPU and wireless local area network module, so improve whole system without line sensitivity.In the present embodiment, described interface is with SDIO interface (SDIO, it is the english abbreviation of Secure Digital Input and Output Card, mean secure digital input-output card, SDIO has defined a kind of Peripheral Interface in standard) describe for example, for the purpose of difference, described interface definition is first group of SDIO interface.
Certainly, also can only on the clock cable SDIO1_CLK of described first group of SDIO interface, take this measure, only reduce the driving force of interface clock signal in first group of SDIO interface, reduce the size of output current, and connecting series impedance build-out resistor on the clock cable SDIO1_CLK of described interface clock signal.Although improving aspect system receptivity not as taking this measure more perfect on whole interface, also the reception of raising system significantly without line sensitivity, meet the designing requirement of whole system.
In like manner, for the connecting interface between CPU and storage card (the SDIO interface of still take describes as example, and is defined as second group of SDIO interface), also can adopt same design.On software, reduce the driving force of second group of SDIO interface or interface clock signal wherein, and connecting on all holding wires of second group of SDIO interface or series impedance build-out resistor on clock cable SDIO3_CLK only, as shown in Figure 2, make CPU and the storage card at holding wire two ends reach impedance matching, with further improve whole system without line sensitivity.
The receptivity of the mobile communication GSM900 frequency range of panel computer and the 2G frequency range of TD-SCDMA of take is below example, by two concrete test cases, is elaborated and is adopted above-mentioned method for designing that the present embodiment proposes at the remarkable result improving aspect system wireless sensitivity.
Embodiment mono-, and the panel computer that adopts mobile communication GSM900 frequency range (reception band limits is 925～960MHz) of take describes as example.
Before the above-mentioned solution that does not adopt the present embodiment to propose, panel computer to be tested, its result is as shown in table 1:
Table 1
From test result, can find out:
1. LCD screen is lighted, and whole channel (frequencies that each channel is corresponding different) is had to impact more than 5dBm, especially 5 channels;
2. wireless local area network module (hereinafter referred to as Wlan module) is opened, very large to 5 channels and 124 channel effect;
3. storage card is carried out to read-write operation, all very obvious on the impact of whole channel.
For interference noise, from interference source, propagation path, sensitive equipment (antenna) three aspects:, set about respectively, make to carry out in the following method analysis and solve.
First, utilize frequency spectrograph, use active probe to search interference source.By after panel computer start, on whole machine, search respectively when LCD screen is lighted, Wlan module is opened, spectrum component during storing card operation, so long as drop on signal in reception frequency range (925～960MHz) scope of panel computer, be approximately greater than-80dBm of intensity, it is all possible interference source.Panel computer model machine for experiment, scanning result is: when light when LCD screen (1), making an uproar at the end of whole reception frequency range, (make an uproar in the end, also claim background noise, refer generally to the overall noise except useful signal in electroacoustics system, noise and ambient noise two parts of comprising system itself) all can lifting, especially near 936MHz, there is a very wide frequency spectrum projection, (specifically can finger mouth conversion chip at CPU and display module, described CPU is undertaken after the matching treatment of signal level by interface conversion chip, connect described LCD screen, more obvious on clock cable LCD_PCLK as shown in Figure 2), (2) open Wlan module, near 960MHz, occur a burr near Wlan module, particularly at the clock cable place of interface, (3) while storage card being carried out to read-write operation, make an uproar and all occur rising and falling in the end of whole reception frequency range, and amplitude is very large, the most obvious near storage card circuit, especially on the clock cable of interface.
Above result is analyzed, and the clock signal LCD_PCLK of display module is digital dock, and frequency is 72MHz, and on circuit board, this clock line is walked on top layer, is easy to radiate form disturb.Its 13 subharmonic are 72MHz*13=936MHz, just in time drop on 5 channel center frequencies, so it is the most obvious to affect the sensitivity of 5 channels when LCD screen is lighted.Impact for the clock frequency of 72MHz on 5 channels, change the operating frequency of display module, for example, change to the clock frequency of 108MHz, its 8 subharmonic are 864MHz, 9 subharmonic are 972MHz, and the system of just in time having avoided panel computer receives frequency range 925～960MHz.Even like this by the harmonic wave interference emission of its generation out, can not affect yet system without line sensitivity.Use after the method, the sensitivity of 5 channels has promoted 5dBm.
Secondly, while lighting due to LCD screen, make an uproar and all raised in the end of whole reception frequency range, so just can affect the sensitivity of whole channel.Through experimental verification be CPU ambient radiation out.The operating frequency of CPU is conventionally in 1GHz left and right, and the operating frequency of DDR memory is approximately 333MHz (triple-frequency harmonics is 999MHz), all very approaching with reception frequency range, thereby generation interference is also apparent.As shown in Figure 5, use shielding material to shield CPU and peripheral circuits thereof, preferably above CPU and peripheral circuit thereof, add radome 1, for the part that does not have conductively-closed cover 1 to cover, can use conductive fabric to wrap up, as added radome 1 or cover conductive fabric above cpu chip, power inductance, DDR memory and the cabling that be connected with them, to avoid by the high-frequency electromagnetic wave excitation of its generation out, forming interference noise.
Again, because the operating frequency of CPU can not be changed (frequency reducing meeting has a huge impact cpu performance), therefore can only try every possible means from propagation path.Found through experiments: the mobile communication antenna 2 of GSM900 is very near with the distance of Wlan antenna 3, shown in Figure 3, Wlan antenna 3 can be as the propagation path disturbing, the interference noise that CPU from mainboard is radiated is incorporated on the mobile communication antenna 2 of GSM900, thereby exerting an influence without line sensitivity to system.Wlan antenna 3 is laid in to the position away from GSM900 mobile communication antenna 2, as shown in Figure 4, use the isolation of two antennas 2,3 of network analyzer test, make the be less than-20dB of isolation between two antennas 2,3, so just reduced the impact of Wlan antenna 3 on the mobile communication antenna 2 of GSM900.Now, during test storage card read-write operation system without line sensitivity, also have significantly and to improve, except 124 channels, other channel all can reach-below 102dBm.
Finally, the interface clock frequency that test Wlan module is connected with CPU, it is the frequency of clock signal SDIO1_CLK, suppose that this clock frequency is 48MHz, its 20 subharmonic is 48MHz*20=960MHz, just in time dropped in the centre frequency of 124 channels, so Wlan module is opened, to affect the sensitivity of 124 channels the most obvious.Use oscilloscope test clock waveform can find to occur overshoot and ringing, this is typical problems of Signal Integrity.Take processing method: on software, reduce the driving force of SDIO interface, can reduce the size of current of whole SDIO interface, also can only reduce the wherein size of current of interface clock signal; On hardware on the holding wire that connects SDIO interface series matching resistor, such as the resistance of 47 ohm, make source reach and mate with terminal.Through processing, waveform overshoot and the ringing of two clock signals obviously improve, and test is without line sensitivity, and impact disappears substantially.Also the SDIO interface that can adopting uses the same method is connected with CPU storage card is processed, with further improve system without line sensitivity.
After several steps are above processed, again test mobile communication GSM900 frequency range panel computer without line sensitivity, its test result ginseng is shown in Table 2:
Table 2
From test result, can find out, when LCD screen is lighted, Wlan module is opened and storage card is carried out to read-write operation, whole system without be all less than-102dBm of line sensitivity, thereby met the designing requirement of the qualified products of national Specification.
Embodiment bis-, and the panel computer that adopts mobile communication TD-SCDMA 2G frequency range (reception band limits is 2010～2025MHz) of take describes as example.
Before the raising that does not adopt the present embodiment to propose is without line sensitivity solution, panel computer to be tested, its result is as shown in table 3:
Table 3
Copy the method described in embodiment mono-, first to the cpu chip on mainboard and peripheral circuit, DDR memory and power inductance and external cabling thereof, adopt the mode that installs radome or parcel conductive fabric additional to shield; The mode that also can adopt radome to combine with conductive fabric shields the frequency electromagnetic waves producing in circuit, first on mainboard, easily produce electromagnetic interference signal device above radome is installed, the part not covering for radome re-uses conductive fabric and wraps up, to avoid electromagenetic wave radiation out to form interference noise, the receptivity of system is impacted.
Then, two groups of SDIO interfaces of CPU connection DDR memory and storage card are processed: the driving force that reduces on the one hand two groups of SDIO interfaces on software; On hardware, set up on the other hand impedance matching resistance and be connected in the holding wire being connected with described SDIO interface, to improve the signal integrity of SDIO interface.
Adopt after above-mentioned measure, although making moderate progress without line sensitivity of system is desirable not enough, without line sensitivity, be still subject to the impact of display module work clock LCD_PCLK.Because the reception band limits of the 2G frequency range of mobile communication TD-SCDMA is 2010～2025MHz, when the frequency of the work clock LCD_PCLK of display module is 72MHz, its 28 subharmonic is 72MHz*28=2016MHz, just in time drop in the centre frequency of 10080 channels, so can causing and having a strong impact on without line sensitivity 10080 channels when LCD screen is lighted.The frequency of the work clock LCD_PCLK of change display module is 108MHz, and its 18 subharmonic is 1944MHz, and 19 subharmonic are 2052MHz, have just in time avoided the reception frequency range 2010～2025MHz of system.Even if the harmonic wave interference emission that the clock cable LCD_PCLK being connected with display module from CPU like this produces is out, can not have influence on yet system without line sensitivity.
Finally, change the distance between Wlan antenna and TD-SCDMA mobile communication antenna, make two be less than-20dB of the isolation between antenna, so just reduced the impact of Wlan antenna on the mobile communication antenna of TD-SCDMA.
Take above-mentioned shielding, improve the signal integrity of SDIO, the frequency of change display module work clock LCD_PCLK is 108MHz, makes after the measures such as mobile communication antenna of Wlan antenna away from TD-SCDMA, test result ginseng is shown in Table 4:
Table 4
From test result above, can find out: use the clock frequency of change display module, commute produces signal integrity that components and parts and the HW High Way of frequency electromagnetic waves shielded, improved interface, make Wlan antenna away from methods such as mobile communication antennas, effectively promoted panel computer without line sensitivity.
Certainly, above-mentioned raising is equally applicable in other Wireless Telecom Equipments except panel computer without the method for line sensitivity, such as smart mobile phone etc.
It should be noted that; the above is only a kind of preferred implementation of the present invention, for those skilled in the art, and under the premise without departing from the principles of the invention; can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.
Claims (8)
1. a method that improves wireless communication system sensitivity, it is characterized in that: in described wireless communication system, include mobile communication antenna, CPU and the display module external with CPU, the clock frequency of CPU and display module communication is set, makes the nth harmonic of this clock frequency and the frequency values of n+1 subharmonic all avoid the reception frequency range of wireless communication system; Described n is positive integer;
In described wireless communication system, also comprise the wireless local area network module being connected with CPU, described CPU connects described wireless local area network module by first group of SDIO interface, reduce the driving force of interface clock signal in first group of SDIO interface, and connecting series impedance build-out resistor on the clock cable of described interface clock signal;
In described wireless communication system, also include storage card, CPU connects described storage card by its second group of SDIO interface, reduce the driving force of interface clock signal in second group of SDIO interface, and connecting series impedance build-out resistor on the clock cable of described interface clock signal.
2. the method for raising wireless communication system according to claim 1 sensitivity, is characterized in that: the clock frequency that described CPU and display module communication are set is 108MHz.
3. the method for raising wireless communication system according to claim 1 sensitivity, it is characterized in that: described wireless local area network module connects Wlan antenna, distance between Wlan antenna and mobile communication antenna is set, makes two be less than-20dB of the isolation between antenna.
4. the method for raising wireless communication system according to claim 1 sensitivity, is characterized in that: reduce the driving force of first group of SDIO interface, and on the holding wire that connects first group of SDIO interface series impedance build-out resistor.
5. the method for raising wireless communication system according to claim 1 sensitivity, is characterized in that: reduce the driving force of second group of SDIO interface, and on the holding wire that connects second group of SDIO interface series impedance build-out resistor.
6. according to the method for the raising wireless communication system sensitivity described in any one in claim 1 to 5, it is characterized in that: in described wireless communication system, also include DDR memory, by parallel bus, connect described CPU, described CPU, DDR memory and be connected to parallel bus between the two above be provided with radome or be coated with conductive fabric.
7. the method for raising wireless communication system according to claim 6 sensitivity, it is characterized in that: in described wireless communication system, also include power module, in described power module, be provided with power inductance, above described power inductance and connected cabling, be provided with radome or be coated with conductive fabric.
8. a wireless communication system, is characterized in that: the method that adopts the raising wireless communication system sensitivity as described in any one claim in claim 1 to 7.
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| CN103813455B (en) * | 2012-11-07 | 2017-09-29 | 中国电信股份有限公司 | Long evolving system parameter optimization distribution method and base station |
| CN105450242A (en) * | 2014-06-30 | 2016-03-30 | 展讯通信（上海）有限公司 | Method and device for improving receiving sensitivity of mobile terminal, and mobile terminal |
| CN104079849A (en) * | 2014-07-14 | 2014-10-01 | 深圳市康凯斯信息技术有限公司 | Television signal receiving device and mobile terminal with same |
| CN105376190B (en) * | 2014-07-31 | 2018-06-05 | 展讯通信（上海）有限公司 | The detection method of communication means and fixed frequency based on GMSK modulation |
| CN105871477A (en) * | 2015-12-11 | 2016-08-17 | 乐视移动智能信息技术（北京）有限公司 | Method and apparatus for resisting to higher harmonic interference of camera MIPI (Mobile Industry Processor Interface) bus and mobile terminal |
| CN105871478A (en) * | 2015-12-11 | 2016-08-17 | 乐视移动智能信息技术（北京）有限公司 | Method and device for resisting high order harmonic interferences of display screen MIPI (Mobile Industry Processor Interface) bus, and mobile terminal |
| CN106027084B (en) * | 2016-05-18 | 2018-12-18 | 昆山龙腾光电有限公司 | Reduce the method and device of noise |
| CN107453837A (en) * | 2016-05-30 | 2017-12-08 | 中兴通讯股份有限公司 | The method of adjustment and device of LCD signal |
| CN106612148A (en) * | 2016-12-15 | 2017-05-03 | 青岛海信移动通信技术股份有限公司 | Method and device for inhibiting interference of working frequency of CPU (Central Processing Unit) to transmitting and receiving module and terminal |
| CN107231201A (en) * | 2017-05-25 | 2017-10-03 | 奇酷互联网络科技（深圳）有限公司 | Alleviate method and electronic equipment of the display screen to antenna interference |
| JP6969974B2 (en) * | 2017-10-23 | 2021-11-24 | トヨタ自動車株式会社 | Key unit |
| CN109743066B (en) * | 2019-02-28 | 2020-12-15 | 重庆蓝岸通讯技术有限公司 | Terminal sensitivity reduction solution method based on camera master clock adjustment, storage medium and terminal |
| CN110299923A (en) * | 2019-06-28 | 2019-10-01 | 联想(北京)有限公司 | A kind of information configuring methods and electronic equipment |
| CN110365842B (en) * | 2019-07-12 | 2021-04-02 | 维沃移动通信有限公司 | Terminal control method and terminal equipment |
| CN110991571A (en) * | 2019-10-30 | 2020-04-10 | 宁波兰羚钢铁实业有限公司 | Material code scanning and warehousing information processing system and method based on ERP system |
| CN112511777B (en) * | 2020-10-30 | 2023-11-10 | 惠州高盛达科技有限公司 | Method for searching interference source of TV on WiFi module |
| CN112787500B (en) * | 2021-01-27 | 2022-11-04 | 展讯通信（上海）有限公司 | Control method, device, system, processor, terminal and medium of DC-DC converter |
| CN114980712B (en) * | 2022-04-26 | 2024-01-19 | 苏州浪潮智能科技有限公司 | Method and device for reducing electromagnetic radiation |
| CN115514437B (en) * | 2022-10-20 | 2023-04-07 | 北京智芯微电子科技有限公司 | Configuration method and configuration device for dual-mode communication fusion and dual-mode communication fusion system |
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